ASTM International - ASTM D2019-97
Standard Test Method for Dirt in Paper and Paperboard
|Publication Date:||10 December 1997|
1.1 This test method (1, 2, 3) is intended for the numerical estimation of dirt in paper or paperboard in terms of equivalent black area. This test method is satisfactory only for the estimation of visual dirtiness and it may be entirely inadequate when the grittiness or other nonvisual effects of dirt are of importance.